Upgrade to ejabberd 19.05
Ejabberd upgrade process
19.05 don't add changes on data or configuration. You may alter your configuration if you want to use new feature to store offline messages in archives anyway. See more details on blogpost.
Schema for MQTT tables was added after 19.02 release despite full support was already available. If you're using MQTT and need SQL backend, in case you dismissed the change, please report to ejabberd 19.02 upgrade note